Pipelines are typically formed and laid in a series of steps that require frequent use of small cranes and side booms, to lift or to lower pipe. The steps are numerous, and time-consuming. Although the pipeline resulting is continuous, the conventional methods of forming and laying the pipeline involve a number of batch processes.
Typically, after the intended path of the pipeline has been located on the ground, a trench is dug at the site, for receiving the pipe. Next, individual pipes are transported to the site, and laid beside the trench. Subsequently, the pipes are picked up, joined into lengths using conventional welding techniques, and inspected. The lengths of welded pipe are coated and then picked up again, to be lowered into the trench. The lengths of welded pipe in the trench are tested, and then the welded pipe lengths are covered.
Where the ground conditions do not permit utilization of a trench (e.g., in a swampy region, or muskeg and tundra), the pipeline may instead be positioned on trestles or other suitable supports in which the pipe is securely held and supported. However, except for the differences in positioning the pipeline relative to the ground, the steps required to form the pipeline are generally the same.
The completed pipeline, although primarily including straight pipe, typically also includes a number of segments that are not straight, and/or include components such as valves that require special handling upon installation.
From the foregoing, it can be seen that the conventional method of forming a pipeline involves personnel with different expertise engaged in a large number of discrete steps, and is somewhat time-consuming as a result.